441821 has 4 divisors (see below), whose sum is σ = 444444. Its totient is φ = 439200.

The previous prime is 441811. The next prime is 441827. The reversal of 441821 is 128144.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19321 + 422500 = 139^2 + 650^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-441821 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 441793 and 441802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (441827) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1040 + ... + 1401.

It is an arithmetic number, because the mean of its divisors is an integer number (111111).

2⁴⁴¹⁸²¹ is an apocalyptic number.

It is an amenable number.

441821 is a deficient number, since it is larger than the sum of its proper divisors (2623).

441821 is a wasteful number, since it uses less digits than its factorization.

441821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2622.

The product of its digits is 256, while the sum is 20.

The square root of 441821 is about 664.6961711940. The cubic root of 441821 is about 76.1638317113.

Adding to 441821 its reverse (128144), we get a palindrome (569965).

The spelling of 441821 in words is "four hundred forty-one thousand, eight hundred twenty-one".